[PATCH V4 3/3] ARM64 LPC: LPC driver implementation on Hip06

[robh@kernel.org (Rob Herring)]

On Thu, Oct 20, 2016 at 05:15:40PM +0800, zhichang.yuan wrote:
> On Hip06, the accesses to LPC peripherals work in an indirect way. A
> corresponding LPC driver configure some registers in LPC master at first, then
> the real accesses on LPC slave devices are finished by the LPC master, which
> is transparent to LPC driver.
> This patch implement the relevant driver for Hip06 LPC. Cooperating with
> indirect-IO, ipmi messages is in service without any changes on ipmi driver.
> 
> Signed-off-by: zhichang.yuan <yuanzhichang@hisilicon.com>
> Signed-off-by: Gabriele Paoloni <gabriele.paoloni@huawei.com>
> ---
>  .../arm/hisilicon/hisilicon-low-pin-count.txt      |  31 ++
>  MAINTAINERS                                        |   8 +
>  drivers/bus/Kconfig                                |   8 +
>  drivers/bus/Makefile                               |   1 +
>  drivers/bus/hisi_lpc.c                             | 501 +++++++++++++++++++++
>  5 files changed, 549 insertions(+)
>  create mode 100644 Documentation/devicetree/bindings/arm/hisilicon/hisilicon-low-pin-count.txt
>  create mode 100644 drivers/bus/hisi_lpc.c
> 
> diff --git a/Documentation/devicetree/bindings/arm/hisilicon/hisilicon-low-pin-count.txt b/Documentation/devicetree/bindings/arm/hisilicon/hisilicon-low-pin-count.txt
> new file mode 100644
> index 0000000..e681419
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/arm/hisilicon/hisilicon-low-pin-count.txt
> @@ -0,0 +1,31 @@
> +Hisilicon Hip06 low-pin-count device
> +  Usually LPC controller is part of PCI host bridge, so the legacy ISA ports
> +  locate on LPC bus can be accessed direclty. But some SoCs have independent
> +  LPC controller, and access the legacy ports by triggering LPC I/O cycles.
> +  Hisilicon Hip06 implements this LPC device.
> +
> +Required properties:
> +- compatible: should be "hisilicon,low-pin-count"

This should be an SoC specific compatible string.

> +- #address-cells: must be 2 which stick to the ISA/EISA binding doc.
> +- #size-cells: must be 1 which stick to the ISA/EISA binding doc.
> +- reg: base memory range where the register set for this device is mapped.
> +
> +Note:
> +  The node name before '@' must be "isa" to represent the binding stick to the
> +  ISA/EISA binding specification.
> +
> +Example:
> +
> +isa at a01b0000 {
> +	compatible = "hisilicom,low-pin-count";
> +	#address-cells = <2>;
> +	#size-cells = <1>;
> +	reg = <0x0 0xa01b0000 0x0 0x1000>;
> +
> +	ipmi0: bt at e4 {
> +		compatible = "ipmi-bt";
> +		device_type = "ipmi";
> +		reg = <0x01 0xe4 0x04>;
> +		status = "disabled";
> +	};
> +};